WSL launcher pure-mode needed

A long-standing deficiency of wsl.exe is that it imposes the console API on the workflow, although most applications, including all Linux applications, do not need it at all, and it inhibits transparent use of WSL by pty-based terminals.
A pure WSL access gateway (also discussed as passthrough mode) is needed to enable seamless and flexible integration of WSL into various local or remote terminal environments.
(Note that in previous issue #9117 the problem was incorrectly related to Windows Terminal which led to complete misinterpretation of the issue.)

Start by reviewing the wsl.exe behavior described in this issue and the prior discussion in issue #9117. Define the requirements for a pure or passthrough access gateway and pty-based terminal integration; done means the agreed workflow no longer imposes the console API on applications that do not need it.

Written by the indexing model from the issue text.